This invention relates generally to dispensers, such as trigger sprayers, and more particularly to dispensers configured for simultaneously dispensing two fluid.
Trigger sprayers are those types of sprayers having pivoting triggers that are manually manipulated to dispense liquids from the sprayers. A conventional trigger sprayer is connected to a liquid container for dispensing the contents of the container as a spray, stream, or foam in response to manual reciprocation of the trigger. This type of trigger sprayer has been employed to dispense various different types of liquids from containers to which the trigger sprayers have been attached. However, such conventional trigger sprayer has drawbacks when employed with certain types of liquids. Certain liquids dispensed from conventional trigger sprayers are the product of two or more separate component liquids that remain stable while separated but have a limited shelf life when they are mixed together. Trigger sprayers attached to containers containing liquids of this type usually cannot remain in storage or on a store shelf for a prolonged period before the liquid product begins to lose effectiveness. To employ conventional trigger sprayers for dispensing liquids of this type and to increase the chance that the shelf life of the liquid product does not expire before the product is sold, the separate liquid components of the final liquid product must be mixed together to produce the final liquid product just prior to the liquid product being packaged in the containers and shipped to market where they are offered for sale. In addition, some liquid products are comprised of one or more component liquids that do not readily mix with each other, for example, water and oil. When liquid products of this type are packaged in containers with trigger sprayers, the separate liquid components that make up the final product tend to separate from each other while the product is stored in inventory or while the product sits on a store shelf awaiting sale. Subsequent operation of the trigger sprayer results in dispensing only that liquid component that had settled to the bottom of the container. In the oil and water example, only the water component of the liquid would be dispensed initially from the sprayer. Once all of the water is dispensed, then oil alone is dispensed.
Various multiple-compartment trigger sprayers have been designed in an effort to overcome the above-noted problems. These new designs include trigger sprayers that are attached to liquid containers that keep the component parts of a liquid product separate from each other until they are drawn from the containers by the trigger sprayers. Trigger sprayers of this type include sprayers that mix the separate component parts of a liquid product for the first time in the pump chambers of the sprayers prior to their being dispensed. However, even these newer designs of trigger sprayers have drawbacks. Once the trigger sprayer pump chamber is primed with the two components of the final liquid product, as the trigger sprayer sits between uses the shelf life of the liquid product in the pump chamber could expire. Also, the separate liquid components of the final product could separate from each other in the sprayer pump chamber. As a result, the next time the trigger sprayer is operated, the liquid first dispensed from the sprayer would be the left-over liquid remaining in the pump chamber. This liquid could have an expired shelf life or separated component liquids. In either situation, the quality of the liquid first dispensed from the sprayer would be less than that expected. Another disadvantage of the present trigger sprayers is that mixed liquids remaining in the trigger sprayers occasionally leaks back into the containers and contaminates the liquids.
A further disadvantage is the complexity of parts required to construct such trigger sprayers. This complexity increases the cost of manufacture and the difficulty of assembling the trigger sprayers.